Electromyelogram recording during surgical operation on the spinal cord in man

Summary

Electric activity of the conduction paths of the spinal cord (electromyelogram — at the level of the cervical, thoracic and superior lumbar segments) was recorded during laminectomy in 10 patients with diseases of the spinal cord.

In leading the potentials of the conduction paths (lateral and posterior stems) of exposed spinal cord a constantly observed rhythm of the background electric activity was present at a rate of 4–8 oscillations per sec, and an amplitude of 20–70 microvolt. Reactive changes of the main rhythm of the electromyelogram noted were the most pronounced at the beginning and at the moment of suspension of proprioceptive stimulation. These changes were associated in a number of observations with the appearance of frequent potentials in the EEG of the parietal and posteroparietal cerebral areas. In the zone directly adjacent to the extramedullary tumor was an attenuation of the main electromyelogram rhythm to 1–2 oscillations per sec. The data obtained should be taken into consideration in developing various methods of preoperative electromyelography for objective determination of the level of the spinal cord effection in man.